British Sea Power: Why is an indie band using 28-piece brass bands on their new album?

The brass concept was first thought up while drinking whisky on an easyJet flight back from Scotland;

New horizon: the wilfully eccentric BSP

“When brass bands started out it was super-modern and the coolest thing you could do was be in a working-class miners' band,” claims British Sea Power frontman Yan Scott Wilkinson. “You got to walk down the street with these instruments made of metal, and they're really loud and in your face.”

It's all about the brass for determinedly idiosyncratic British Sea Power, with their latest record, Sea of Brass, infused with cornets, trombones and flugel horns. The album combines the “quirky” Brighton-based indie band alongside championship 28-piece brass orchestras from around the UK (including the esteemed Redbridge Brass Band), with arranger Peter Wraight creating brass parts to accompany a selection of BSP tracks from their back-catalogue.

It began life as a Derby Council arts commission and a one-off gig, before morphing into an album, a limited-edition box set and more concerts. Quick-witted Wilkinson and guitarist Martin Noble, the creative hub of BSP, whom I meet in a Hove pub around the corner from their homes, appear genuinely baffled by the turn of events. The brass concept was first thought up while drinking whisky on an easyJet flight back from Scotland; “It was never a childhood dream,” Wilkinson quips, which he does a lot.

“Initially we wanted an epic feel,” maintains softly spoken Noble, who like Wilkinson is from Cumbria. “But as the process went along and we got a bit of feedback, we thought 'God, that's not what we imagined.'”

“Sometimes we had to lose whole brass sections, in order to bring our songs back,” says Noble. “Peter Wraight wanted to show off brass bands so much that he sort out of tramped all over the original songs, but the final eight songs on the album achieved what we set out to do.”

“It's okay to be trampled occasionally,” Wilkinson mischievously interjects.

The end result works beautifully. For the most part the brass element is understated, the instruments don't overwhelm (or trample) British Sea Power's radiant material. The brass orchestras lend their songs a solemn drama and poignancy that recall Richard Hawley circa Coles Corner, particularly the haunting “When a Warm Wind Blows Through the Glass” and “No Need to Cry” (which features on their limited-edition box set). The brass instruments even deliver a grand, James Bond-style quality, especially combined with Wilkinson's soaring, Tim Booth-like voice on the piquant lament “What You Need the Most”, also on the limited box set.

It's a success then for this risky and wilfully eccentric band, who feature eight-foot dancing bears (although these have been sadly axed for the brass concerts), foliage and fairy lights at their concerts, have performed at an East Sussex seaside café and the Natural History Museum, and have been known to provide interviewers with grid references in order to locate them. Laid-back Noble and Wilkinson are by no means “zany”, however, and are more interested in discussing science documentaries (Vice's The Iceman), allotments (Noble campaigned for his allotment not to be sold off), birdspotting (BSP's songs often reference birds: “Don't You Want to Be a Bird?”, “The Guillemot Girls” and “The Great Skua”, which is a highlight on the new record), Russian politics, unnecessary wars (“Newspapers have done quite a bad job in the past few years, like not stopping us going to war”) and Jeremy Coybyn's Labour leadership victory.

“The fact that a lot of people don't like Corbyn being elected is reaffirming to me,” maintains Wilkinson. “You can believe in him, you can believe in what he's saying, I agree with a lot of what he's saying. He's quite sensible. It's nice to have someone who's normal and doesn't wave his arms around all the time, like Tony Blair did.”

BSP, for all their quirkiness, have never shied away from politics or controversy, with the sensational pro-immigration track “Waving Flags” (“So welcome in/ We are Barbarians/ Oh welcome in/ Across the Carpathians”) from 2008's Do You Like Rock Music? proving a prime and prescient example.

“Yet again we were ahead of our time,” says Wilkinson. “We wrote it because the Eastern European people coming to England at that time were getting slagged off, you know 'why are all the Polish people stealing our jobs?' Well, because they do them properly and they're nice. My thing is I quite like Europe and I like people of different cultures and we now get food we didn't get 20 years ago, which is good.”

“There's a loads of nonsense about stealing jobs,” he continues. “Immigration is good, it generates money and it generates culture, it's a cultural exchange.”

Last year they reissued The Decline of British Sea Power on their own label, Golden Chariot, with Wilkinson claiming, “We made a small profit, if we split it between us we could probably go out for a curry or something.” So, the bold direction towards brass makes sense, and Wraight showed them the “sort of textures and moods brass orchestras can generate”.

“Wraight calls them brass orchestras, he didn't like calling them brass bands,” says Wilkinson. “There's more to them than just doing Christmas carols and they want to show off what they can do with different frequencies.”

“A brass instrument will go from one to 10, and the average rock band will go from three to seven. In a nutshell they're very dynamic.” Wilkinson agrees: “It's fantastic music, not at all soft, it's like happy hardcore or something.”

'Sea of Brass' is out 30 October on Rough Trade